1. Field of Invention
The present invention relates generally to a printing system for selectively printing with dye-based ink and/or pigment-based ink and, more specifically, to a print head for such a printing system, the print head including two (or more) pigment-based black pens, a dye-based black pen, and a plurality of color pens.
2. Description of the Related Art
Print heads in color inkjet printers are typically arranged with their pens in the sequence, KCMY, where: K=pigmented black, C=cyan, M=magenta, and Y=yellow. Recently, print heads have been developed to accommodate other arrangements such as photo printing with six inks, for example, the pen arrangement, KCcl YMml, where: cl=light cyan and ml=light magenta.
Other print head arrangements have been employed for dry time purposes. In U.S. Pat. No. 6,132,021 to Smith et al. (incorporated herein by reference), the pen arrangement, CKMY, allows over and under printing of cyan and magenta in order to improve the dry time of the pigmented black ink while printing in a bi-directional manner. However, this arrangement can allow hue shift on the black when printed in a bi-directional manner due to the use of cyan as under printing and magenta as overprinting in one direction, and magenta as under printing and cyan as overprinting in the other printing direction (FIG. 6A).
For the purposes of this disclosure, xe2x80x9cType Axe2x80x9d media is any paper or coated media that can accept pigmented inks, e.g., HP Premium Matte Brochure Paper. xe2x80x9cType Bxe2x80x9d media is any photo media that does not accept pigmented inks, e.g., HP Premium Photographic Plus.
Although various print head arrangements exist, there is a need for a printer system which includes all inks on its carriage needed to function as both a high-speed office printer and as a high-quality photographic printer without user intervention (i.e., without manually changing the print heads and cartridges). Also, it would be desirable for such a printer system to selectively energize dye-based and/or pigment-based ink pens on its carriage depending upon the type of media being printed on.
The printing system of the present invention is configured to selectively print with dye-based and/or pigment-based inks to accommodate different types of media. The printing system includes a print head arrangement with both dye-based and pigment-based inks on the carriage. For example, a print head arrangement according to the present invention includes two (or more) pigment-based black pens, a dye-based black pen, and a plurality of color pens. The dye-based black ink is a composite black (approximately equal parts of cyan, magenta and yellow) or a xe2x80x9ctruexe2x80x9d dye-based black ink which allows for more efficient use of ink. With less ink on the media, dry time is reduced, the possibility of printing flaws such as coalescence (where the ink exceeds the ability of the media to xe2x80x9cprocessxe2x80x9d the ink quantity and the ink droplets tend to clump or coalesce together) is reduced, and photo quality is improved by providing a darker black.
In accordance with one embodiment of the present invention, a printing system for selectively printing with different types of ink includes: a plurality of ink dispensers including two or more pigment-based black ink dispensers and a dye-based black ink dispenser; and a controller configured to generate ink dispenser control signals to selectively energize the ink dispensers. In a preferred embodiment, the controller is configured to generate the ink dispenser control signals to selectively energize the pigment-based black ink dispensers and the dye-based black ink dispenser depending upon the type of media being printed on. In a preferred embodiment, the plurality of ink dispensers include six ink dispensers arranged in a sequence, KABCMY, K being the dye-based black ink dispenser, A and B being the pigment-based black ink dispensers, C being a dye-based cyan ink dispenser, M being a dye-based magenta ink dispenser, and Y being a dye-based yellow ink dispenser. In a preferred embodiment, the controller is configured to generate the ink dispenser control signals to energize the dye-based black ink dispenser (K), the pigment-based black ink dispensers (A, B), the dye-based cyan ink dispenser (C), the dye-based magenta ink dispenser (M) and/or the dye-based yellow ink dispenser (Y) to print text, graphics and/or an image. In a preferred embodiment, the controller is configured to generate the ink dispenser control signals to alternately energize the pigment-based black ink dispensers (A, B). In a preferred embodiment, the controller is configured to generate the ink dispenser control signals to energize the dye-based black ink dispenser (K) to under print. In a preferred embodiment, the controller is configured to generate the ink dispenser control signals to energize the dye-based cyan ink dispenser (C) and the dye-based magenta ink dispenser (M) to under print. In a preferred embodiment, the controller is configured to generate the ink dispenser control signals to energize the dye-based black ink dispenser (K) to under print and the dye-based cyan ink dispenser (C) and the dye-based magenta ink dispenser (M) to overprint, or vice versa.
In accordance with another embodiment of the present invention, a printing system for selectively printing with different types of ink includes: a plurality of ink dispensers including a dye-based black ink dispenser (K), two pigment-based black ink dispensers (A, B) and a plurality of colored ink dispensers; and a controller configured to generate ink dispenser control signals which energize the ink dispensers, the ink dispenser control signals being generated to selectively energize the dye-based black ink dispenser (K) and the pigment-based black ink dispensers (A, B) depending upon the type of media being printed on. In a preferred embodiment, the pigment-based black ink dispensers (A, B) are positioned adjacent to each other. In a preferred embodiment, the plurality of colored ink dispensers include a cyan ink dispenser (C) and a magenta ink dispenser (M), and the plurality of ink dispensers are arranged linearly such that the dye-based black ink dispenser (K) is positioned on one side of the pigment-based black ink dispensers (A, B), and the cyan ink dispenser (C) and the magenta ink dispenser (M) are positioned on another side of the pigment-based black ink dispensers (A, B). In a preferred embodiment, the controller is configured to generate the ink dispenser control signals to energize the dye-based black ink dispenser (K), the pigment-based black ink dispensers (A, B) and/or the colored ink dispensers to print text, graphics and/or an image. In a preferred embodiment, the controller is configured to generate the ink dispenser control signals to alternately energize the pigment-based black ink dispensers (A, B). In a preferred embodiment, the controller is configured to generate the ink dispenser control signals to energize the dye-based black ink dispenser (K) to under print. In a preferred embodiment, the controller is configured to generate the ink dispenser control signals to energize the dye-based cyan ink dispenser (C) and the dye-based magenta ink dispenser (M) to under print. In a preferred embodiment, the controller is configured to generate the ink dispenser control signals to energize the dye-based black ink dispenser (K) to under print and the dye-based cyan ink dispenser (C) and the dye-based magenta ink dispenser (M) to overprint, or vice versa.
In accordance with another embodiment of the present invention, a printing system for selectively printing with different types of ink includes: a plurality of ink dispensers including dye-based and pigment-based ink dispensers; and a controller configured to generate ink dispenser control signals which energize the ink dispensers, the ink dispenser control signals being generated to selectively energize the dye-based and pigment-based ink dispensers depending upon the type of media, being printed on without user intervention to replace print heads and/or cartridges of the printing system.
The above described and many other features and attendant advantages of the present invention will become apparent as the invention becomes better understood by reference to the following detailed description when considered in conjunction with the accompanying drawings.